Investigation of Magnetic Properties of Zn Doped Y-Type Barium Ferrite

Jung Tae Lim,Chul Sung Kim

doi:10.1109/tmag.2013.2250930

Abstract

The Ba 2 Co 2-x Zn x Fe 12 O 22 (x = 0.0$, 0.5, 1.0, 1.5, and 2.0) polycrystalline samples were synthesized by the solid-state reaction method. Based on the Rietveld refinement, the crystal structures of samples were found to be single-phased and determined to be rhombohedral with space group of R - 3m. The unit cell volume (V u ) of the samples increased with increasing Zn ion concentration. In the magnetic phase diagram of Ba 2 Co 2-x Zn x Fe 12 O 22 system, samples with x ≤ 1.5 showed the spin transitions both at T s and T C . For x = 2.0 sample, we observed the disappearance T s . The non-magnetic Zn ions preferentially occupy the tetrahedral sublattices of 6c IV *, and 6c IV * with down-spin site. At low temperature, this leads to the increase in M s . However, the experimentally measured M s at 295 K shows a slight decrease around x = 1.5. In - ddition, we have measured Mössbauer spectra of samples at various temperatures ranging from 4.2 to 750 K, which can analyzed with six-sextets for Fe sites corresponding to the 3b VI , 6c IV *, 6c VI , 18h VI , 6c IV , and 3α VI of the Y-type hexagonal crystallographic sites. From the Mössbauer spectra of 295 K, we observed the line-width broadening with increasing Zn concentration.

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